Islamic State of Iraq and the Levant

The Islamic State of Iraq and Syria, also known as the Islamic State of Iraq and the Levant, or by the abbreviations ISIS or ISIL, is a jihadist militant group in Iraq and Syria. Founded in 2010, the organization succeeded the Islamic State of Iraq and in 2014 took over most of northern Iraq. Its leader Abu Bakr al-Baghdadi declared himself Caliph of the "Islamic State" on 29 June 2014.

History
The Islamic State of Iraq and Syria/the Levant was founded in 2010 by Abu Bakr al-Baghdadi, who took over the Islamic State of Iraq after the death of Abu Omar al-Baghdadi. The group, headquartered in Ar-Raqqah (near Aleppo, Syria), operated in Iraq, Syria, Turkey, and Lebanon, and allied with Harakat Sham al-Islam and Suqour al-Ezz. The group fought the Syrian Army, Free Syrian Army, Iraqi Army, Turkish Army, Hezbollah, and the Peshmerga, taking a role in the civil wars in both Iraq and Syria.

On 5 June 2014, ISIS launched an offensive in northern Iraq, gaining the support of many Sunnis. The Sunnis were offended by the Shiite-dominated Iraqi government, and most of them volunteered to join ISIS. ISIS even had propaganda videos in different languages, calling on Islamic people from across the world to join the struggle against the Iraqi and Syrian governments.

On 29 June 2014, having overrun Tikrit, Mosul, Nasiriyah, Fallujah, and Baiji, Al-Baghdadi declared himself the Caliph of the "Islamic State" and called on all Muslim extremist groups to pledge allegiance to the new caliphate.